1. Baowu Group Echeng Iron and Steel Co.， Ltd.， Ezhou 436002， China；
2. Research and Development Center of Baosteel lron and Steel Co., Ltd., Wuhan 430080， China
Abstract：In order to find out the reason of unqualified impact at the center of thick quenched and tempered high strength ship plate, the composition and microstructure of the core sample were analyzed by means of spectrometer, microscope and SEMEDS. The results showed that the reason for the unqualified impact at the center was the presence of largesize MnS inclusions, Nb and Ti inclusions, as well as more Al2O3 inclusions and Mg, Ca and other foreign inclusions. The analysis suggested that, through the measures such as improving the cleanliness of molten steel, avoiding secondary oxidation pollution, controlling ladle furnace (LF) refining cycle and operation, reducing the degree of superheat of molten steel, optimizing the electromagnetic stirring and soft reduction process, and adopting the slow cooling for stacking, the internal quality of the slab could be improved, and meanwhile, the central segregation and inclusions could be reduced. At the same time, the core impact toughness could be effectively improved by properly optimizing the slab heating, rolling and heat treatment process.
王孝东，余宏伟，张开广，鲍海燕，张欢，易勋. 厚规格调质高强度船板心部冲击不合格原因分析[J]. 物理测试, 2021, 39(3): 48-.
WANG Xiaodong，YU Hongwei，ZHANG Kaiguang，BAO Haiyan，ZHANG Huan,YI Xun. Cause analysis of unqualified impact at the center of thick quenched and tempered high strength ship plate. PHYSICS EXAMINATION AND TESTING, 2021, 39(3): 48-.
2021, Vol. 39 
